In rats, the allele for long whiskers is dominant to the allele for short whiskers. at another gene locus, a dominant allele produces whiskers and the recessive allele produces a rat with no whiskers. the alleles at these 2 gene loci assort independently. if a rat that is homozygous for both recessive alleles is crossed with a rat that is heterozygous at both gene loci, what percentage of the offspring are expected to have short whiskers? ( enter the number only without the percent sign. for example, enter 100% as 100 and enter 12.5% as 12.5 )

Blood made up of red and white blood cells work together to form

Elements and compounds are pure substances that cannot be broken down physically into a simpler substance. a physical change doesn’t break the bonds between atoms of a substance or form new ones. compounds can be broken down by a chemical change. a chemical change breaks chemical bonds and/or forms new ones between atoms of a substance. what simple substance would a compound break into? the basic elements that make it up! for example, if you passed a very strong electric current through water you’d break the chemical bonds in water and be left with oxygen and hydrogen. which of the following is an example of a chemical change? a separating water into different glasses b breaking frozen ice cubes with a hammer c running an electric current through water d boiling water to evaporate it on a stove

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.